bash read a if

[kocek.kvetoslav na vestizol.cz]

Ahoj,

mam v bashi takovouto konstrukci:

read

if [ $REPLY == "a" ] || [ $REPLY == "A" ]; then
echo $REPLY
fi


pokud na vyzvu read zadam a, A, nebo cokoliv jineho dela to,
co ma. Ale pokud nezadam nic, vyplivne na me:

line 20: [: ==: unary operator expected
line 20: [: ==: unary operator expected

Cim to? Jak 100hoven?
dik za radu
-- 
 Kosac